/*******************************************************************************
* Copyright (c) 2000, 2009 IBM Corporation and others.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* IBM Corporation - initial API and implementation
*******************************************************************************/
package org.eclipse.swt.widgets;
import org.eclipse.swt.internal.cocoa.*;
import org.eclipse.swt.*;
import org.eclipse.swt.graphics.*;
/**
* Instances of this class provide an i-beam that is typically used
* as the insertion point for text.
*
* - Styles:
* - (none)
* - Events:
* - (none)
*
*
* IMPORTANT: This class is intended to be subclassed only
* within the SWT implementation.
*
*
* @see Caret snippets
* @see SWT Example: ControlExample, Canvas tab
* @see Sample code and further information
* @noextend This class is not intended to be subclassed by clients.
*/
public class Caret extends Widget {
Canvas parent;
int x, y, width, height;
boolean isVisible, isShowing;
int blinkRate;
Image image;
Font font;
static final int DEFAULT_WIDTH = 1;
/**
* Constructs a new instance of this class given its parent
* and a style value describing its behavior and appearance.
*
* The style value is either one of the style constants defined in
* class SWT
which is applicable to instances of this
* class, or must be built by bitwise OR'ing together
* (that is, using the int
"|" operator) two or more
* of those SWT
style constants. The class description
* lists the style constants that are applicable to the class.
* Style bits are also inherited from superclasses.
*
*
* @param parent a composite control which will be the parent of the new instance (cannot be null)
* @param style the style of control to construct
*
* @exception IllegalArgumentException
* - ERROR_NULL_ARGUMENT - if the parent is null
*
* @exception SWTException
* - ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the parent
* - ERROR_INVALID_SUBCLASS - if this class is not an allowed subclass
*
*
* @see SWT
* @see Widget#checkSubclass
* @see Widget#getStyle
*/
public Caret (Canvas parent, int style) {
super (parent, style);
this.parent = parent;
createWidget ();
}
boolean blinkCaret () {
if (!isVisible) return true;
if (!isShowing) return showCaret ();
if (blinkRate == 0) return true;
return hideCaret ();
}
void createWidget () {
super.createWidget ();
blinkRate = display.getCaretBlinkTime ();
isVisible = true;
if (parent.getCaret () == null) {
parent.setCaret (this);
}
}
boolean drawCaret () {
if (parent == null) return false;
if (parent.isDisposed ()) return false;
int nWidth = width, nHeight = height;
if (nWidth <= 0) nWidth = DEFAULT_WIDTH;
if (image != null) {
NSSize size = image.handle.size();
nWidth = (int)size.width;
nHeight = (int)size.height;
}
NSRect rect = new NSRect();
rect.x = x;
rect.y = y;
rect.width = nWidth;
rect.height = nHeight;
parent.view.setNeedsDisplayInRect(rect);
return true;
}
/**
* Returns a rectangle describing the receiver's size and location
* relative to its parent (or its display if its parent is null).
*
* @return the receiver's bounding rectangle
*
* @exception SWTException
* - ERROR_WIDGET_DISPOSED - if the receiver has been disposed
* - ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
*
*/
public Rectangle getBounds () {
checkWidget();
if (image != null) {
Rectangle rect = image.getBounds ();
return new Rectangle (x, y, rect.width, rect.height);
} else {
if (width == 0) {
return new Rectangle (x, y, DEFAULT_WIDTH, height);
}
}
return new Rectangle (x, y, width, height);
}
/**
* Returns the font that the receiver will use to paint textual information.
*
* @return the receiver's font
*
* @exception SWTException
* - ERROR_WIDGET_DISPOSED - if the receiver has been disposed
* - ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
*
*/
public Font getFont () {
checkWidget();
if (font != null) return font;
return parent.getFont ();
}
/**
* Returns the image that the receiver will use to paint the caret.
*
* @return the receiver's image
*
* @exception SWTException
* - ERROR_WIDGET_DISPOSED - if the receiver has been disposed
* - ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
*
*/
public Image getImage () {
checkWidget();
return image;
}
/**
* Returns a point describing the receiver's location relative
* to its parent (or its display if its parent is null).
*
* @return the receiver's location
*
* @exception SWTException
* - ERROR_WIDGET_DISPOSED - if the receiver has been disposed
* - ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
*
*/
public Point getLocation () {
checkWidget();
return new Point (x, y);
}
/**
* Returns the receiver's parent, which must be a Canvas
.
*
* @return the receiver's parent
*
* @exception SWTException
* - ERROR_WIDGET_DISPOSED - if the receiver has been disposed
* - ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
*
*/
public Canvas getParent () {
checkWidget();
return parent;
}
/**
* Returns a point describing the receiver's size.
*
* @return the receiver's size
*
* @exception SWTException
* - ERROR_WIDGET_DISPOSED - if the receiver has been disposed
* - ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
*
*/
public Point getSize () {
checkWidget();
if (image != null) {
Rectangle rect = image.getBounds ();
return new Point (rect.width, rect.height);
} else {
if (width == 0) {
return new Point (DEFAULT_WIDTH, height);
}
}
return new Point (width, height);
}
/**
* Returns true
if the receiver is visible, and
* false
otherwise.
*
* If one of the receiver's ancestors is not visible or some
* other condition makes the receiver not visible, this method
* may still indicate that it is considered visible even though
* it may not actually be showing.
*
*
* @return the receiver's visibility state
*
* @exception SWTException
* - ERROR_WIDGET_DISPOSED - if the receiver has been disposed
* - ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
*
*/
public boolean getVisible () {
checkWidget();
return isVisible;
}
boolean hideCaret () {
if (!isShowing) return true;
isShowing = false;
return drawCaret ();
}
/**
* Returns true
if the receiver is visible and all
* of the receiver's ancestors are visible and false
* otherwise.
*
* @return the receiver's visibility state
*
* @exception SWTException
* - ERROR_WIDGET_DISPOSED - if the receiver has been disposed
* - ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
*
*
* @see #getVisible
*/
public boolean isVisible () {
checkWidget();
return isVisible && parent.isVisible () && parent.hasFocus ();
}
boolean isFocusCaret () {
return this == display.currentCaret;
}
void killFocus () {
if (display.currentCaret != this) return;
display.setCurrentCaret (null);
if (isVisible) hideCaret ();
}
void releaseParent () {
super.releaseParent ();
if (this == parent.getCaret ()) parent.setCaret (null);
}
void releaseWidget () {
super.releaseWidget ();
if (display.currentCaret == this) {
hideCaret ();
display.setCurrentCaret (null);
}
parent = null;
image = null;
}
/**
* Sets the receiver's size and location to the rectangular
* area specified by the arguments. The x
and
* y
arguments are relative to the receiver's
* parent (or its display if its parent is null).
*
* @param x the new x coordinate for the receiver
* @param y the new y coordinate for the receiver
* @param width the new width for the receiver
* @param height the new height for the receiver
*
* @exception SWTException
* - ERROR_WIDGET_DISPOSED - if the receiver has been disposed
* - ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
*
*/
public void setBounds (int x, int y, int width, int height) {
checkWidget();
if (this.x == x && this.y == y && this.width == width && this.height == height) return;
boolean isFocus = isFocusCaret ();
if (isFocus && isVisible) hideCaret ();
this.x = x;
this.y = y;
this.width = width;
this.height = height;
if (isFocus && isVisible) showCaret ();
}
/**
* Sets the receiver's size and location to the rectangular
* area specified by the argument. The x
and
* y
fields of the rectangle are relative to
* the receiver's parent (or its display if its parent is null).
*
* @param rect the new bounds for the receiver
*
* @exception SWTException
* - ERROR_WIDGET_DISPOSED - if the receiver has been disposed
* - ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
*
*/
public void setBounds (Rectangle rect) {
checkWidget();
if (rect == null) error (SWT.ERROR_NULL_ARGUMENT);
setBounds (rect.x, rect.y, rect.width, rect.height);
}
void setFocus () {
if (display.currentCaret == this) return;
display.setCurrentCaret (this);
if (isVisible) showCaret ();
}
/**
* Sets the font that the receiver will use to paint textual information
* to the font specified by the argument, or to the default font for that
* kind of control if the argument is null.
*
* @param font the new font (or null)
*
* @exception IllegalArgumentException
* - ERROR_INVALID_ARGUMENT - if the font has been disposed
*
* @exception SWTException
* - ERROR_WIDGET_DISPOSED - if the receiver has been disposed
* - ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
*
*/
public void setFont (Font font) {
checkWidget();
if (font != null && font.isDisposed ()) {
error (SWT.ERROR_INVALID_ARGUMENT);
}
this.font = font;
}
/**
* Sets the image that the receiver will use to paint the caret
* to the image specified by the argument, or to the default
* which is a filled rectangle if the argument is null
*
* @param image the new image (or null)
*
* @exception IllegalArgumentException
* - ERROR_INVALID_ARGUMENT - if the image has been disposed
*
* @exception SWTException
* - ERROR_WIDGET_DISPOSED - if the receiver has been disposed
* - ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
*
*/
public void setImage (Image image) {
checkWidget();
if (image != null && image.isDisposed ()) {
error (SWT.ERROR_INVALID_ARGUMENT);
}
boolean isFocus = isFocusCaret ();
if (isFocus && isVisible) hideCaret ();
this.image = image;
if (isFocus && isVisible) showCaret ();
}
/**
* Sets the receiver's location to the point specified by
* the arguments which are relative to the receiver's
* parent (or its display if its parent is null).
*
* @param x the new x coordinate for the receiver
* @param y the new y coordinate for the receiver
*
* @exception SWTException
* - ERROR_WIDGET_DISPOSED - if the receiver has been disposed
* - ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
*
*/
public void setLocation (int x, int y) {
checkWidget();
setBounds (x, y, width, height);
}
/**
* Sets the receiver's location to the point specified by
* the argument which is relative to the receiver's
* parent (or its display if its parent is null).
*
* @param location the new location for the receiver
*
* @exception SWTException
* - ERROR_WIDGET_DISPOSED - if the receiver has been disposed
* - ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
*
*/
public void setLocation (Point location) {
checkWidget();
if (location == null) error (SWT.ERROR_NULL_ARGUMENT);
setLocation (location.x, location.y);
}
/**
* Sets the receiver's size to the point specified by the arguments.
*
* @param width the new width for the receiver
* @param height the new height for the receiver
*
* @exception SWTException
* - ERROR_WIDGET_DISPOSED - if the receiver has been disposed
* - ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
*
*/
public void setSize (int width, int height) {
checkWidget();
setBounds (x, y, width, height);
}
/**
* Sets the receiver's size to the point specified by the argument.
*
* @param size the new extent for the receiver
*
* @exception IllegalArgumentException
* - ERROR_NULL_ARGUMENT - if the point is null
*
* @exception SWTException
* - ERROR_WIDGET_DISPOSED - if the receiver has been disposed
* - ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
*
*/
public void setSize (Point size) {
checkWidget();
if (size == null) error (SWT.ERROR_NULL_ARGUMENT);
setSize (size.x, size.y);
}
/**
* Marks the receiver as visible if the argument is true
,
* and marks it invisible otherwise.
*
* If one of the receiver's ancestors is not visible or some
* other condition makes the receiver not visible, marking
* it visible may not actually cause it to be displayed.
*
*
* @param visible the new visibility state
*
* @exception SWTException
* - ERROR_WIDGET_DISPOSED - if the receiver has been disposed
* - ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
*
*/
public void setVisible (boolean visible) {
checkWidget();
if (visible == isVisible) return;
isVisible = visible;
if (!isFocusCaret ()) return;
if (isVisible) {
showCaret ();
} else {
hideCaret ();
}
}
boolean showCaret () {
if (isShowing) return true;
isShowing = true;
return drawCaret ();
}
}